Three dimensional mapping of turbid media by hyper spectral imaging

医学成像诊断中的非侵入性模式对于最小化患者的风险至关重要，特别是因为许多疾病需要重复成像。此外，为了防止高成本妨碍定期检查，需要快速且具有成本效益的成像模式。理想情况下，这些方法还应该能够实现无标签成像，因为标签对患者具有潜在的副作用，例如过敏。此外，开发合适的标记物是一个昂贵且耗时的过程。高光谱成像系统具有实现快速、低成本、非侵入性和无标记成像的潜力。因此，它们为克服上述所有挑战提供了机会。因此，计划中的研究项目的目标是汇编和研究将高光谱图像转换为三维组织图像的方法。导致组织中的穿透深度的波长依赖性的两种机制将用于此：组织成分（诸如血红蛋白和水）中的波长依赖性吸收以及组织的波长依赖性散射行为。在本项目范围内，对不同的转化方法进行了调查和评价。因此，一种用于检查恶性近表面组织改变的光学非侵入性模式被期望，这也为医生提供了一个大的视野。与已建立的光学3D重建方法如光学相干断层扫描相比，新方法不仅具有测量和分析折射率和散射变化的优点，而且还具有吸收率变化的优点。因此，吸收剂浓度变化，例如癌组织和健康组织中的血液量或散射浓度变化，这意味着血管和周围组织中的散射体的量应该是可检测的。散射和吸收体改变的可检测性与深度分辨图像的重建的这种组合保证了对恶性地下改变的改进检测。通过特定深度的图像不再与所有其他深度卷积的事实来简化检测。这将显著增加对比度，并且由于消除了组织改变的可能伪装，因此应该能够进行更可靠的诊断。此外，由于成像方法是无接触的，并且使用标准白色光源进行照明，因此它将能够对患者进行低风险和廉价的重复检查。

Non-invasive modalities in medical imaging diagnostics are of vital importance in order to minimize the risks for patients, particularly since many diseases necessitate repetitive imaging. Furthermore, preventing high costs from impeding regular examinations, fast and cost-efficient imaging modalities are needed. Ideally, these methods should also enable label free imaging, as labels bear potential side effects for the patients such as allergies. Furthermore, the development of suitable markers is a costly and time-consuming process. Hyperspectral imaging systems have the potential to enable fast, low-cost, non-invasive and label free imaging. Thus, they provide the opportunity to overcome all the mentioned challenges. Therefore, the goal of the planned research project is to compile and to investigate methods for the transformation of hyperspectral images into three-dimensional tissue images. Two mechanisms leading to a wavelength dependency of the penetration depth in tissue will be used for this: the wavelength dependent absorption in tissue constituents such as hemoglobin and water as well the wavelength dependent scattering behavior of the tissue. Within the scope of this project different transformation approaches are investigated and evaluated. As outcome, an optical non-invasive modality for the examination of malign near-surface tissue alterations is expected which also provides the doctor with a large field of view.Compared to established optical 3D reconstruction methods such as Optical Coherence Tomography, the new approach has the advantage of not only measuring and analyzing changes in refractive index and scattering, but also changes in absorptivity. Therefore, absorber concentration changes, such as the amount of blood in cancerous and healthy tissue or scattering concentration changes, this means the amount of scatterers in blood vessel and surrounding tissue, should be detectable. This combination of the detectability of scattering and absorber alterations and the reconstruction of the in-depth resolved images promises improved detection of malign subsurface alterations. The detection is simplified by the fact that the images of a specific depth are not convoluted with all other depths anymore. This should increase the contrast significantly and it should enable a more reliable diagnosis since possible disguises of tissue alterations are removed. Furthermore, since the imaging approach is contact free and uses standard white light sources for illumination, it will enable low-risk and inexpensive repetitive examinations of patients.